Layered assemblies

ABSTRACT

An assembly structure is formed of generally rigid layers of material bonded to generally flexible layers so as to form apparatus including hinges, bearings, and other translating and rotating subunits along with embedded functional devices.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. nonprovisionalapplication Ser. No. 16/431,476 filed on Jun. 4, 2019 which in turn is acontinuation of U.S. nonprovisional application Ser. No. 14/834,336filed on Aug. 24, 2015 (now issued U.S. Pat. No. 10,349,543), which inturn is a continuation-in-part of PCT patent application numberPCT/US2014/018096, filed on Feb. 24, 2014, which in turn claims thebenefit of U.S. provisional patent application No. 61/768,397 filed onFeb. 22, 2013; and of U.S. provisional patent application No. 61/768,494filed on Feb. 24, 2013; and of U.S. provisional patent application No.61/771,847 filed on Mar. 2, 2013; and of U.S. provisional patentapplication No. 61/772,239 filed on Mar. 4, 2013; and of U.S.provisional patent application No. 61/772,257 filed on Mar. 4, 2013; andof U.S. provisional patent application No. 61/775,852 filed on Mar. 11,2013; and of U.S. provisional patent application No. 61/775,867 filed onMar. 11, 2013; and of U.S. provisional patent application No. 61/788,698filed on Mar. 15, 2013; and of U.S. provisional patent application No.61/821,495 filed on May 9, 2013; and of U.S. provisional patentapplication No. 61/933,027 filed on Jan. 29, 2014; and of U.S.provisional patent application No. 61/933,037 filed on Jan. 29, 2014.The present application is a continuation of U.S. nonprovisionalapplication Ser. No. 16/431,476 filed on Jun. 4, 2019 which in turn is acontinuation of U.S. nonprovisional application Ser. No. 14/834,336filed on Aug. 24, 2015 (now issued U.S. Pat. No. 10,349,543) which inturn claims the benefit of U.S. provisional patent application No.62/051,355 filed Sep. 17, 2014. The disclosures of all of the foregoingapplications are incorporated by reference herewith in their entireties.

FIELD OF THE INVENTION

The present invention relates features of a manufactured assembly andmore particularly to assembly features of a manufactured laminatedassembly.

BACKGROUND

The ability to manufacture goods efficiently and with superiorfunctionality has long been a key determinant of economic success forindividuals, enterprises and societies. Contrary to popular perception,most innovation takes place through an evolutionary process in whichpre-existing elements are recombined in surprisingly useful ways, ratherthan as a radical departure from the status quo. This is true ofinnovations in apparatus and methods and also in manufacturingtechniques.

The history of manufactured goods spans a long series of transitionsacross materials (from wood, stone and leather to gold, copper, bronze,iron and steel and on to various synthetic materials including amongothers man-made polymers. Likewise, the techniques of manufacturing haveevolved from the preparation of individual items through the developmentof interchangeable parts, moving assembly lines and variousphotolithographic techniques for the preparation of circuit boards,integrated circuits and micro-electromechanical (MEMS) systems.

MEMS systems predominate among mechanical devices at the micron scaleand typically involve the bulk addition and removal of materials inserial fashion from a single substantially planar substrate. Traditionalmachining and fabrication practices are readily applicable to devicesfrom centimeter scale up to meters (e.g. large machine tools anddynamos).

While these developments have led to a remarkable abundance and varietyof products, one that would astound the most prescient individual of acentury ago, there remain apparatus and systems that are persistentlydifficult, time-consuming and consequently expensive to manufacture. Inparticular, manufacturing at the millimeter scale, remains challengingfor a variety of reasons.

SUMMARY

Having examined and understood a range of previously available devices,the inventor of the present invention has developed a new and importantunderstanding of the problems associated with the prior art and, out ofthis novel understanding, has developed new and useful solutions andimproved devices, including solutions and devices yielding surprisingand beneficial results.

Certain exemplary structures, prepared according to principles of theinvention, will include laminated structures created from substantiallyflat source layers of material. Three-dimensional assemblies are formedthrough subtractive machining and additive lamination of these flatlayers. Such a methodology creates two and a half dimensional structuresbuilt from the layers. In addition, certain three-dimensional structureswill be added to the assembly for their beneficial effect.

The invention encompassing these new and useful solutions and improveddevices is described below in its various aspects with reference toseveral exemplary embodiments including a preferred embodiment.

These and other advantages and features of the invention will be morereadily understood in relation to the following detailed description ofthe invention, which is provided in conjunction with the accompanyingdrawings. It should be noted that, while the various figures of thefollowing drawings show respective aspects of the invention, no onefigure is intended to show the entire invention. Rather, the figurestogether illustrate the invention in its various aspects and principles.As such, it should not be presumed that any particular figure isexclusively related to a discrete aspect or species of the invention. Tothe contrary, one of skill in the art will appreciate that the figurestaken together reflect various embodiments exemplifying the invention.

Correspondingly, referenced throughout the specification to “oneembodiment” or “an embodiment” means that a particular feature,structure, or characteristic described in connection with the embodimentis included in at least one embodiment of the present invention. Thus,the appearance of the phrases “in one embodiment” or “in an embodiment”in various places throughout the specification are not necessarily allreferring to the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows, in schematic perspective view, a portion of a laminatedassembly including a tendon feature prepared according to principles ofthe invention;

FIG. 2 shows, in schematic perspective view, a portion of a furtherlaminated assembly including a tendon feature;

FIG. 3 shows, in the form of a linear flowchart, a portion of a methodfor preparing a laminated assembly according to principles of theinvention;

FIG. 4A shows, in exploded schematic perspective view, a laminatedassembly prepared according to principles of the invention;

FIG. 4B shows, in schematic perspective view, a portion of a laminatedassembly prepared according to principles of the invention;

FIG. 5 shows, in schematic perspective view, further aspects of alaminated assembly prepared according to principles of the invention;

FIG. 6 shows, in schematic perspective view, still further aspects of alaminated assembly prepared according to principles of the invention;

FIG. 7A shows, in exploded schematic side view, a portion of an assemblyincluding an elastic portion prepared according to principles of theinvention;

FIG. 7B shows, in schematic side view, a portion of an assemblyincluding a deformed elastic portion prepared according to principles ofthe invention;

FIG. 7C shows, in schematic side view, a portion of an assemblyincluding a relaxed elastic portion prepared according to principles ofthe invention;

FIG. 8 shows, in photographic perspective view, various manufacturedcomponents exemplifying possible configuration features for applicationto an elastic portion for inclusion in an assembly prepared according toprinciples of the invention;

FIG. 9 shows, in schematic perspective view, a portion of an assemblyincluding a torsion hinge prepared according to principles of theinvention;

FIG. 10A shows, in schematic perspective view, a further portion of anassembly including a torsion hinge prepared according to principles ofthe invention;

FIG. 10B shows, in schematic perspective view, a still further portionof an assembly including a torsion hinge prepared according toprinciples of the invention;

FIG. 11 shows, in schematic perspective view, a portion of an assemblyincluding a torsion hinge having a fiber prepared according toprinciples of the invention;

FIG. 12A shows, in schematic top view, a portion of an assemblyincluding a fastening device prepared according to principles of theinvention;

FIG. 12B shows, in schematic exploded side view, a portion of anassembly including a fastening device prepared according to principlesof the invention;

FIG. 12C shows, in schematic exploded side view, further aspects of anassembly including a fastening device prepared according to principlesof the invention;

FIG. 13 shows, in cutaway perspective view, a portion of a bearingdevice for use in an assembly prepared according to principles of theinvention;

FIG. 14 shows, in schematic side view, an assembly including a bearingdevice prepared according to principles of the invention

FIG. 15A shows, in schematic side view, a portion of a bearing devicefor use in an assembly prepared according to principles of theinvention;

FIG. 15B shows, in schematic side view, a portion of a further bearingdevice for use in an assembly prepared according to principles of theinvention;

FIG. 15C shows, in photographic top view, a portion of a mechanicaldevice including a bearing device exemplary of a device that can be usedan assembly prepared according to principles of the invention;

FIG. 16A shows, in schematic perspective view, a portion of a laminatedassembly including a hinge feature prepared according to principles ofthe invention;

FIG. 16B shows, in schematic side view, a portion of a laminatedassembly including an un-clamped hinge feature prepared according toprinciples of the invention;

FIG. 16C shows, in schematic side view, a portion of a laminatedassembly including a clamped hinge feature prepared according toprinciples of the invention;

FIG. 17A shows, in schematic side view, a portion of a laminatedassembly including a further clamped hinge feature prepared according toprinciples of the invention;

FIG. 17B shows, in schematic side view, a portion of a laminatedassembly including a still further clamped hinge feature preparedaccording to principles of the invention;

FIG. 17C shows, in schematic side view, a portion of a laminatedassembly including yet another clamped hinge feature prepared accordingto principles of the invention;

FIG. 18A shows, in schematic perspective view, a portion of a laminatedassembly including a hinge feature prepared according to principles ofthe invention;

FIG. 18B shows, in schematic side view, a portion of a laminatedassembly including an un-clamped hinge feature prepared according toprinciples of the invention;

FIG. 18C shows, in schematic side view, a portion of a laminatedassembly including a clamped hinge feature prepared according toprinciples of the invention;

FIG. 18D shows, in schematic side view, a portion of a laminatedassembly including a further clamped hinge feature prepared according toprinciples of the invention;

FIG. 19 shows, in kinematic diagram form, certain features of alaminated assembly including a hinge feature prepared according toprinciples of the invention;

FIGS. 20A and 20B show in graphical form, information related to theoperation of a laminated assembly including a hinge feature preparedaccording to principles of the invention;

FIG. 21 shows, in schematic diagram form, certain features of alaminated assembly including a further hinge feature prepared accordingto principles of the invention;

FIG. 22 shows, in schematic perspective view, certain aspects andfeatures of a laminated assembly including a hinge feature preparedaccording to principles of the invention;

FIG. 23 shows, in schematic diagram form, certain aspects and featuresof a laminated assembly including a further hinge feature preparedaccording to principles of the invention;

FIGS. 24A, 24B, 24C and 24D show, in schematic perspective view, variousoperational states of a laminated assembly including a Sarrus hingefeature prepared according to principles of the invention.

FIG. 25 shows, in cross-section, a further laminated assembly includinga relaxed hinge feature prepared according to principles of theinvention;

FIG. 26 shows in cross-section, a further portion of a laminatedassembly including a flexed hinge feature prepared according toprinciples of the invention;

FIG. 27 shows, in cross-section, a portion of a still further laminatedassembly including a hinge feature prepared according to principles ofthe invention; and

FIG. 28 shows, in perspective view, a further laminated assemblyincluding a relaxed hinge feature prepared according to principles ofthe invention.

DETAILED DESCRIPTION

The following description is provided to enable any person skilled inthe art to make and use the disclosed inventions and sets forth the bestmodes presently contemplated by the inventor of carrying out hisinventions. For purposes of explanation, numerous specific details areset forth in order to provide a thorough understanding of the presentinvention. It will be apparent, however, to one skilled in the art thatthe invention may be practiced without these specific details. Incertain instances, well-known structures and devices are shown in blockdiagram form in order to avoid unnecessarily obscuring the substancedisclosed.

It is in the context of these difficulties, well-known and of longstanding in the art, that the present inventor has come to recognize afundamental opportunity with surprising and beneficial ramifications.The methods described herein are extremely versatile with respect to thematerials that can be used. For example, traditional MEMS are largelylimited to bulk addition of materials, whereas the methods describedherein can be used not only to add precisely patterned layers, but alsofull sub-components, such as integrated circuits, flex circuits,actuators, batteries, etc. The thermal requirements of the multi-layer,super-planar structures described herein can also be much lower, and thefabrication-equipment costs can be much lower, as well. Further still,processing steps in these methods on the various layers can be performedsimultaneously and parallel, allowing important scalability of themanufacturing process.

The present invention includes a complement of methods and apparatusthat together form and identify a novel set of interoperable componentsand subassemblies. This set of components and subassemblies, appliedalone, in combination, and together with additional elements, enable thepreparation of mechanical and electromechanical devices with aconsistency of characteristics, customizability and manufacturingscalability that would otherwise be difficult or impossible to achieve.

In its various aspects and embodiments, the invention includescomponents, subassemblies and assemblies that incorporate laminatedcombinations of generally planar materials. Among other notablefeatures, the invention includes members having certain structuralcharacteristics in one or more dimensions and referred to as “tendons”or “cable drives,” and features having various characteristics andconfigurations arranged to support a relative rotary motion between twoelements around at least one axis and referred to as “hinges” or“joints.” Among these, are included a variety of “torsion joints” asexemplified herewithin. Also included are “rivets” and riveted features,“embedded circuits and devices” and “3-D layers” that deform, uponrelaxation or under applied force, to assume a non-planar aspect.

Taken together, these methods, apparatus and systems are referred to asMicro Multilayer Etched Composite Systems™ (μMECS™).

In light of the foregoing, FIG. 1 shows, in schematic perspective view,a portion of a joint assembly 100 prepared according to principles ofthe invention. The illustrated joint assembly 100 includes a firstsubstantially rigid portion 102 mutually coupled to a secondsubstantially rigid portion 104 by an intervening joint element 106. Thejoint element 106 permits a rotary motion 108 of portion 104 withrespect to portion 102 about a longitudinal axis 110 of the jointelement.

A tendon member 112 is substantially fixedly coupled at a first endregion thereof to portion 104 by an anchor feature 114. The tendonmember 112 is slidingly coupled to portion 102 at a further region by aguide feature 116 such that a variable length 118 of tendon member 112is disposed between the anchor feature 114 and a guide feature 116. Afurther length 120 of tendon member 112 extends outward beyond the guidefeature 116.

The tendon member 112 serves to transmit mechanical force to and acrossthe joint. The tendon can take many forms but is typically compliant inbending and constructed of a material that can slide through arespective tendon guide feature 116 with low friction. Accordingly, incertain embodiments, a tendon will be relatively inelastic along alongitudinal axis 122 while being relatively flexible across axis 122.

In alternative embodiments, a tendon may exhibit desirable longitudinalelasticity along axis 122. In certain applications, such longitudinalelasticity will serve to absorb shock that might otherwise be damagingto other features of the joint or apparatus in general.

FIG. 2 shows a further embodiment 200 in which a unitary tendon 202spans a plurality of joint elements e.g., 204, 206 so as to operate morethan one joint at once. In a fashion similar to that of joint assembly100, tendon 202 is anchored to a first substantially rigid member 208 byan anchor feature 210 at or near one end of the tendon.

The tendon passes slidingly through one or more joint guide featurese.g., 212, 214 coupled to a second substantially rigid member 216, andthrough a further joint guide feature 218 coupled to still anothersubstantially rigid member 220. The application of a tensile force 222along a longitudinal axis 224 of the tendon actuates the assembly toproduce a rotation of the substantially rigid members about the jointelements.

A μMECS™ tendon, as illustrated and described in relation to FIGS. 1 and2 , can be prepared according to a manufacturing process like thatillustrated schematically in FIG. 3 . FIG. 3 shows a block diagramcorresponding to the steps of a manufacturing process 300. Beginning atstep 302, the process involves forming a pattern in one or moregenerally planar sheets of a more or less rigid material 304. In atypical application, at least one of the sheets will be substantiallyrigid. In certain applications, the generally rigid material may have ananisotropic characteristic such that it is more or less rigid along oneaxis than along another.

In various applications, the sheet will include a material such as, forexample, fiberglass reinforced polyester, carbon reinforced polyester,or any other filled or reinforced polymer material. Alternately or incombination, the generally rigid material may include a metallicmaterial such any appropriate metal or metallic alloy. The forming of apattern in such a sheet of material will include, in certain exemplaryapplications, the removal of material by photolithographic etching, theremoval of material by laser machining, patterning of the material bythe application of a die and/or the removal of material by theapplication of a cutting tool. In addition, additive processes may beused in forming the patterned sheet.

As noted, at step 304, a pattern is formed in one or more sheets of agenerally planar flexible component material. In various applications,the generally flexible material may be substantially flexible. Incertain applications, the flexible material may have an anisotropiccharacteristic such that it is more or less flexible along one axis thanalong another. Patterning of the generally flexible material willproceed in any manner appropriate to the material including, amongothers, any of the processes identified above with respect to the rigidmaterial.

At step 306, a pattern is formed in one or more sheets of an adhesivecomponent material. In various cases, the adhesive material may besubstantially flexible. In other cases, the adhesive material will besubstantially rigid. In certain cases, the adhesive material may have ananisotropic characteristic such that it is more or less flexible orrigid along one axis than along another. Patterning of the adhesivematerial will proceed in any manner appropriate to the adhesive materialincluding, among others, any of the processes identified above withrespect to the rigid and flexible materials.

As indicated at step 310, fixturing apparatus is provided for alignmentof the various sheets of rigid, flexible and adhesive material preparedin steps 304-308. In certain abundance, the fixturing apparatus willinclude alignment pins such as are known in the art. In otherembodiments the fixturing apparatus will include active alignmentactuators and/or optical alignment devices.

As indicated in step 312, an assembly is thereafter prepared by applyingthe previously prepared and patterned (and in some cases unpatternedsheets of material) to the fixturing apparatus. It will be appreciatedthat the patterns and materials will, in certain embodiments, differfrom sheet to sheet according to the requirements of a particularapplication. Moreover, in certain cases, one or more sheets of adhesivematerial may be omitted in favor of applying adhesive individual sheetsand/or surface regions. The adhesive material will be applied, in anymanner that is no more becomes known in the art. By way of example only,the adhesive material may be applied in liquid, powder, aerosol orgaseous form as individual sheets are added to the assembly.

As will be understood by one of ordinary skill in the art in light ofthe totality of the current presentation, the characteristics of thevarious layers and patterns will be chosen and applied according to therequirements of a particular assembly being prepared. Thus, for example,where a joint feature is required, a prepared void in substantiallyrigid sheets above and below a flexible layer will leave a portion of anintervening flexible layer exposed and ultimately able to flexiblysupport the adjacent more rigid materials.

As indicated in step 314, curing conditions are then applied to theassembled materials and/or fixturing apparatus. In certain embodiments,the curing conditions will include the application of heat and/orpressure to the assembly of layers. In other embodiments, the curingconditions will include the application of physical or chemicaladditives such as, for example, catalytic chemicals, reducetemperatures, gaseous chemical components, or any other conditionappropriate to secure a desirable unification of the various layers intoan integrated assembly.

As per step 316, the integrated assembly is, in certain embodiments,then removed from the fixturing apparatus. In some embodiments theintegrated assembly is transferred thereafter to additional fixturingequipment. In other embodiments, and as will be understood by one ofskill in the art, the integrated assembly remains on the fixturingapparatus for further processing.

In step 318, a method according to certain embodiments of the inventionwill include the removal of certain portions of one or more of the rigidand/or flexible layers. These portions will have served to supportparticular regions of the corresponding layer during the precedingprocessing steps. Their removal will allow one or more of those portionsto translate, rotate, or otherwise reorient with respect to someadditional portion of the assembly. This step may include the removal ofindividual assemblies from a larger sheet/assembly on which multipleassemblies of similar or different configurations have been prepared.

In certain embodiments, the removal of particular support regions willbe effected by laser machining. In various other embodiments, theremoval of support regions will be effected by mechanical machining, wetchemical etching, chemical vapor etching, scribing, cutting, diecutting, punching, and/or tearing, among others. One of skill in the artwill appreciate that any combination of these methods (or other methodsthat are known or become known in the art) will be beneficially appliedand will fall within the scope of the invention.

Once the removal of identified portions of the one or more rigid and/orflexible layers is complete, the assembly is activated, as per step 320to transition from its existing status to a post-activationconfiguration. This activation will, in certain embodiments, includingreorientation of certain portions of one or more regions of one or moreof the sheets of material. Thus, for example, in certain embodiments, aportion of the assembly will fold up out of its initial plane to form athree-dimensional assembly in the manner of a pop-up book.

The activation will incorporate various motions in correspondingembodiments of the invention including various translations androtations along and about one or more axes. In respective embodiments,the activation will be effected by active fixturing apparatus, by theaction of an individual worker, by a robotic device, by a deviceintegrated within the assembly itself such as, for example, a spring, amotor, a piezoelectric actuator, a bimetal/bimorph device, a magneticactuator, electromagnetic actuator, a thermal expansive or contractivedevice, chemical reaction including, for example, a gas generatingprocess, the crystallization process, a dehydration process, apolymerization process, or any other processor device appropriate to therequirements of a particular application.

In certain embodiments, and as indicated at step 322, a further processstep will secure the apparatus in its activated configuration. Amongother methods that will be evident to one of skill in the art in lightof the present disclosure, this step of securing the apparatus in itsactivated configuration will include, in certain embodiments, pointsoldering, wave soldering, tip soldering, wire bonding, electricalwelding, laser welding, ultrasonic welding, thermal bonding, chemicaladhesive bonding, the activation of a ratchet and pawl device, theactivation of a helical unidirectional gripping device, the applicationof a snap, a hook and loop fastener, a rivet, or any other fastener orfastening method that is known or becomes known to those of skill in theart.

Of course it will be understood by the reader that in certainembodiments, the process or mechanism that reorients the apparatus intoits activated configuration will serve to maintain that configurationwithout any additional step 322 process or action. Moreover, while thesecuring indicated at step 322 is generally anticipated to be permanent,in certain applications it will be beneficially temporary and/orrepeatable.

At step 324 additional scaffolding elements will be removed or severedto release the activated and secured from any remaining scaffolding. Oneof skill in the art will appreciate that this step will be unnecessarywhere the device was completely released from any associated scaffoldingprior to activation. Moreover, in other embodiments and applications theactivated device will remain coupled to surrounding scaffolding foradditional processing steps. To the extent that step 324 is applied anyof the approaches and methodologies identified above at, for example,step 318 will be advantageously applied according to the instantcircumstances.

Thereafter, again depending on the requirements of a particularapparatus or embodiment, various testing, packaging, systems integrationand other manufacturing or application steps will be applied asindicated in step 326 after which the operation concludes with step 328.

FIG. 4A shows certain elements 400 of an assembly consisted with, forexample, process 300. The elements include a first patternedsubstantially rigid layer 402, a second patterned substantially rigidlayer 404, a patterned substantially flexible layer 406, and first 408and second 410 patterned adhesive layers.

As shown, the pattern of each exemplary layer includes apertures, e.g.,412, 414 for receiving corresponding fixturing pins or dowels, e.g.,416, 418. These fixturing dowels serve to maintain a desirable alignmentof the various patterns while the assembly is compressed and curing ofthe adhesive layers 408, 410 is accomplished.

The result, as shown 430 in FIG. 4B is an exemplary hinged assembly 432that has been released from a surrounding scaffolding material 434 bythe severing of various support regions, e.g., 436. As is readilyapparent the released assembly includes a hinge feature 438 coupledbetween first 440 and second 442 substantially rigid members. As furthershown in the magnified portion region 444, each substantially rigidmember includes an upper rigid portion 446 and a lower rigid portion 448coupled to respective sides of the flexible portion 450 by respectivelayers of cured, or otherwise activated, adhesive material 452, 454. Itwill be further appreciated that, while no securing step is apparent inrelation to the hinged assembly 432, other assemblies will benefit fromsuch further processing.

Referring again to FIG. 1 , and FIG. 4B, and in the context of thefurther disclosure above, it will be apparent to one of skill in the artthat, for example, a hinged assembly 432 can be prepared including ananchor feature 114 and a guide feature 116 along with a tendon member112. Reference is made, for example, to FIG. 5 .

FIG. 5 shows, in schematic perspective view, a further hinged assembly500 including a first substantially rigid member 502 and a secondsubstantially rigid member 504 mutually coupled to one another by ahinge feature 506. An anchor feature 508 is coupled to an upper surfaceregion 510 of substantially rigid member 504.

The anchor feature is formed to include portions 512, 514 of respectivefurther substantially rigid layers. Portion 512 is substantially fixedlycoupled to upper surface 510 by a portion 516 of a further adhesivelayer. Portion 514 is coupled to portion 516 by a portion 518 yetanother adhesive layer.

Respective upper and lower surface regions at a distal end 520 of atendon member 522 are substantially fixedly coupled to correspondingregions of adhesive layers 518 and 516 and thereby fixed tosubstantially rigid member 510 in the vicinity of anchor feature 508.

Similarly, a tendon guide feature 524 is coupled to an upper surfaceregion 526 of rigid member 502. The attendant guide feature 524 includessubstantially rigid portion 527 forms of the same material layer asportion 512. Likewise, portion 528 of tendon guide feature 524 is formedof the same substantially rigid layer as portion 514 of the anchorfeature 508.

Adhesive layer portion 530 is formed of the same layer as portion 516and couples portion 527 to surface region 526. Likewise, adhesive layerportion 532 is formed of the same adhesive layer as portion 518, andsubstantially fixedly couples rigid portion 528 to rigid portion 527.Finally, it should be noted, that the adhesive layers forming portions530 and 532 are pattern so as to avoid any bonding between tendon member522 and adjacent surface regions of the tendon guide feature 524 and/orsurface region 526.

In the illustrated embodiment, tendon member 522 includes asubstantially inelastic, substantially flexible material with surfacecharacteristics that allow it to slide with minimal friction acrosssurface region 526 and the internal surface regions of tendon guidefeature 524. Consequently, the application of a tensile force 534 to aproximal region of the tendon member 522 causes rigid member 504 torotate with respect to rigid member 502 about the hinge feature 506.

Tendons can be patterned from full sheets of materials includingpolyimide films and steel, or can be inserted into μMECS™ layups asdiscrete fibers or fiber bundles of aramid or other material. Thisinvention fundamentally enables a new class of tendon-driven mechanismsthat includes robust and complex prosthetic limbs

The above-described tendon stands in contrast to an alternativearrangement in which a rigid or nearly rigid mechanical structure isemployed as a linkage. The link is generally includes a substantiallyrigid member disposed between opposite sides of a hinge or joint withlocalized flexible portion that respective ends of the rigid mechanicalstructure.

One use for μMECS™ tendons is in conjunction with more conventionallinkage structures. These tendons allow mapping complex actuator strokesto similarly complex mechanical linkage kinematics in a simple, robustfashion. Generally operated in tension, a tendon prepared according toprinciples of the invention offer, among other benefits, the advantagesof simple power transmission from a proximal actuator to a distal endeffector through extremely complex geometries with minimal increases inmechanical footprint, mass, and complexity.

In certain embodiments, the tendon member 522 will include an insulatingmaterial such as, for example, polyimide or polyester (soldcommercially, for example as Mylar™). In other embodiments, the tendonmember 522 will be formed of a conductive material such as, for examplea metallic material. In still further embodiments, the tendon member 522will include both insulating and conductive materials and, in certainembodiments, will include patterned conductors in the form of a flexibleprinted circuit. Similarly, other flexible and rigid members within anassembly according to the invention can include flexible conductorsformed using the known methods of printed circuit technology. Suchconductors can be employed to convey signals and power to and fromdevices embedded within the assembly.

FIG. 6 illustrates such an assembly 600 including a first substantiallyrigid portion 602 mutually coupled to a second substantially rigidportion 604 by a hinge feature 606. A device such as, for example, anelectronic device 608 is disposed within a cavity 610 formed within anupper layer 612 of substantially rigid portion 604. First 614 and second616 printed circuit style conductors are disposed on an upper surface618 of a tendon member 620. Conductors exported at 616 are operativelysignalingly coupled to further printed circuit style conductors e.g.,622 disposed on an upper surface of upper layer 612 by way of printedcircuit vias, as are known in the printed circuit arts. In theillustrated embodiment, a wire bond, e.g. 624 couples conducted 622 to acorresponding contact on the electronic device 608.

It will be appreciated that, while the example discussed above refers toelectrical conductors other communications means will be employed inalternative embodiments of the invention. Thus, for example, opticalsignal conductors, pneumatic signal conductors, hydraulic signalconductors, and any other appropriate means for conducting power and/orinformation within and across the inventive assembly is contemplated tobe within the scope of the invention.

In various embodiments, the electronic device 608 will include, forexample, one or more of a microprocessor, a microcontroller, a quantumcomputer, a dedicated logic device such as a programmable logic device(PLA), or a memory device any of which are of any configuration known,or that becomes known, in the art. Moreover, the electronic device 608will also, in certain embodiments, include one or more of anaccelerometer, a micro-electromechanical (MEMS) system a chemical orbiological analysis device such as a microfluidic analysis device, orany other device, electronic or otherwise, advantageously employedaccording to a desirable embodiment of the invention. In still furtherembodiments, the device 608 will not be purel electronic, but photonic(such as, for example and without imitation a red laser gyroscopesubsystem, a laser subsystem or the photochemical subsystem) or may bepurely optical, such as a purely optical computer device.

It will also be appreciated that, in certain moments of the invention,the device 608 will be bound within cavity 610 by an adhesion between alower surface thereof and a region of adhesive layer 626. In otherembodiments, the device 608 will be held in place by other means suchas, for example and without limitation, a spring clip or an overlyinglayer of rigid or flexible material.

Of course it will be appreciated that pre-formed or standard circuitboard and flexible circuit assemblies will be embedded within certainembodiments of the invention. It will also be appreciated that existingprinted circuit techniques and apparatus will be employed in the presentnew context with surprising and beneficial results.

FIGS. 7A 70 and 7C show, in schematic elevation, further aspects of anassembly and device 700 prepared according to principles of theinvention. Assembly 700 includes a layer 702 having a three-dimensionalor “3-D” aspect or feature 704. In the illustrated embodiment, the layer702 is shown as a layer of spring steel and the 3-D feature 704 is acurved spring deformation of the layer that tends to flatten out whensubjected to sufficient external pressure, but to resume a curved aspectwhen the external pressure is released. It will be appreciated by thereader, however, that a wide variety of devices and materials will beapplicable to present a 3-D aspect according to principles of theinvention.

Some of these, like the spring steel, will be elastic in nature. Otherswill have an active characteristic and still others will besubstantially elastic but assume a 3-D aspect in response to an externalstimulus as where, for example, a sheet metal alloy device resumes anearlier configuration when exposed to a temperature within a particularrange of temperatures.

In light of the foregoing discussion, and with further reference to FIG.7A it is readily apparent that the assembly 700 includes substantiallyrigid layers 706, 708 and 710. Substantially flexible layer 712 isdisposed between layers 706 and 708 and between corresponding adhesivelayers 714 and 716. Generally elastic (here's spring steel) layer 702 isdisposed between substantially rigid layers 708 and 710 and betweencorresponding adhesive layers 718 and 720. It will be appreciated thatall of the layers are viewed in side view and, in fact, would extendinto the plane of the drawing.

Prior to assembly, the generally elastic layer 702 includes adeformation or curvature 704. It will be appreciated that, if uppersurface 722 of generally elastic layer 702 extends in a first dimension724 within the plane of the drawing and in a second dimension 726 intothe plane of the drawing, the deformation or curvature 704 extends thelayer 702 into a third dimension 728, also in the plane of the drawing;hence the designation of layer 702 as a “3-D” layer.

As shown in FIG. 7A prior to assembly curvature 704 is unencumbered andfully extended. Referring, for example, to process 300 (as discussedabove), it will be appreciated that various layers of assembly 700 willbe aligned (typically employing alignment/fixturing apparatus) andcompressed during a bonding process. The compressor force is appliedduring bonding and as part of the curing conditions will tend to do formthe material of layer 700 and flatten curvature 704 into a planarconfiguration.

Thus, as shown in FIG. 7B layer 702 and, indeed, all of the layers ofthe assembly 700 exhibit a substantially planar aspect with essentiallyno deviation in dimension 728. In particular, region 704 issubstantially flattened and an exposed region 730 of substantiallyflexible layer 712 is also disposed in a substantially coplanarorientation with respect to the balance of layer 712.

Once during its complete, however, and the assembly 700 is released fromany fixturing apparatus, and any necessary action is taken to releasethe assembly 700 from any surrounding scaffolding material, a differentcondition ensues. As shown in FIG. 7C because of its springcharacteristic, region 704 tends to resume its pre-existing curvatureurging a lower surface 732 of layer 708 away from an upper surface 734of layer 710. However, because assembly portion 736 is typically coupledto the balance of the assembly 700 by exposed region 730 ofsubstantially flexible layer 712 surface region 732 tends to pivot 738,as shown.

Thereafter, assembly portion 736 will respond generally elastic way toan applied force 740. One of skill in the art will appreciate thepotential for applying such an assembly in the development of a widevariety of devices such as, for example and without limitation, a haptickeyboard, a limit switch, an audio transducer, accelerometer, a shockabsorbers, and any of the wide variety of other devices and systems allof which are considered to be within the scope of the present invention.

Source layers with three-dimensional structures will include, insertembodiments, “formed layers” that can be created by a variety of means.In certain embodiments, one will start with a flat source sheet that canattain three-dimensional structure through a variety of processesincluding, but not limited to: selective depth etching, selective depthmachining, 3-D printing, describing, die stamping, embossing and rollforming. Such 3-D layers really add to the capability of a laminateddevice. For example they allow the inclusion of springs, clips,electrical contacts, gripping surfaces, latches, tabs, corrugatedelements, stiffened element, and much more. Of particular utility is anexpanded ability to store elastic energy within a laminate. Elasticmaterials with three dimensional features can be fully or partially“flattened” during lamination, storing energy. After lamination,flattened features can be used to apply forces with force componentsperpendicular to the laminate.

Without in any way intending to limit the scope of this disclosure, FIG.8 illustrates a variety of exemplary configurations into which amaterial such as, for example, spring steel, can be formed to provide athree-dimensional configuration. It should also be noted that theplacement of magnets within an assembly 700 can provide and affectcorresponding to a “3-D” layer by supplying a localized magnetic fieldsto effect a desirable attraction or repulsion between portions of anassembly.

Other applications of magnets within an assembly prepared according tothe invention include providing forces effective to activate theassembly into a folded 3-D state, and forces effective to lock theassembly in an assembled state or any other desirable state eitherfixedly and terminally, or temporarily and/or repeatably. One of skillin the art will appreciate that one or more pre-magnetite elements canbe deposited within respective cavities provided in various layers ofassembly (comparable to cavity 610 of FIG. 6 ). Alternately, particularregions of a magnetizable layer will, in some embodiments, be magnetizedin situ before after bonding of the layers within the assembly. In stillother embodiments, a layer of particulate material deposited betweenlayers will include a magnetic characteristic, either in advance ofassembly, or as a result of post-assembly magnetization.

Still other applications for magnets within such an assembly includesensing and signaling of a particular state or orientation of an elementof an assembly prepared according to principles of the invention. Thus,a magnet disposed within a portion of assembly may be used to activate asensor such as, for example, a magnetic reed switch or a Hall effecttransducer.

FIG. 9 illustrates a further aspect of an exemplary assembly preparedaccording to principles of the invention and shows part of a torsionjoint 900. The torsion joint 900 includes a flexure beam portion 902that is subject to a simple bending torque during operation of thejoint. In various embodiments, the flexure beam 902 will include one ormore of a generally planar flexure material, a fiber, a bundle offibers, a ribbon, a woven textile strap, or any other appropriateconfiguration and material effective to produce the required rotation904 of a first generally rigid member 906 with respect to a secondgenerally rigid member 908 about a longitudinal axis 910.

In the illustrated embodiment, torsion joint 900 also includes aplurality of interleaved extensions, e.g., 912, 914, 916, 918, 920. Theflexure beam 902 is typically disposed in respective distal ends of theextensions. The extensions, as well as the generally rigid members 906,908 include first 922 and second 924 layers of substantially rigidmaterial with a layer 926 of more or less elastic material, from whichthe flexure beam portion 902 is formed, disposed between thesubstantially rigid layers.

Although not expressly identified in FIG. 9 , it is to be understoodthat, in at least some embodiments, additional layers of adhesivematerial are disposed between the layers 922, 924 and layer 926. Theseadditional layers of adhesive material serve to bond the entire assemblytogether.

One of skill in the art will understand that the rotation 904 of member906 with respect to member 908 can result in high stresses on theflexure beam portion 902. Under some circumstances, the stresses canresult in your fracture and/or plastic deformation of the flexure beammaterial. Accordingly, in certain embodiments, it will be desirable toprovide a mechanical stop to prevent over-rotation of the torsion jointand thus avoid premature failure of the assembly as a whole.

FIG. 10A shows the basic unit of a torsion joint 1000 includinginterleaved extended support regions 1002, 1004, 1006 and a flexibleflexure beam 1008.

FIG. 10B Illustrates an advanced torsion joint using multiple attachmentpoints 1020, 1022, 1024, 1026, 1028, 1030, 1032, 1034, 1036 for greateroff-axis stability.

It will also be noted that a torsion joint repaired according toprinciples of the invention will, in certain embodiments and dependingon particular materials and dimensions employed, have a high springconstant and may not exhibit your rotation. Again, in certainapplications these characteristics will be advantageously employed.

In the torsion topology, the joint rotates with the restoring force muchlower than that resulting from a bending topology. This can enablelow-torque operation for delicate mechanisms such as mechanical watchactions. Conversely, this apology enables use of stiffer and more robustjoint materials, such as spring steel and other metals, while limitingthe torque needed to actuate the device.

Symmetry about the axis leads to a joint trajectory closer to yourrotation than other designs. Lower stresses in the joint material alsoincreased mechanical efficiency by reducing loss to degeneration.

Torsional joints can be created by including fibers or fiber bundlesinto the layout. Alternately, a fiber reinforced polymer can be used asa flexible layer. Optionally, the polymer can be dissolved in asubsequent process to leave the fiber or fiber bundle behind. FIG. 11shows a torsion joint 1100 including a fiber 1102 as a flexure beam.

In the illustrated embodiment, the flexure beam fiber 1102 has asubstantially circular cross-section. In other embodiments of theinvention, however, the flexure beam fiber will have any of a widevariety of cross-sectional configurations including, for example andwithout limitation, a triangular cross-section, square cross-section, apentagonal cross-section, a hexagonal cross-section, a heptagonalcross-section, or any other political cross-section appropriate to aparticular application. In addition, in certain embodiments, the flexurebeam fiber will have an elliptical cross-section, a stellatecross-section, or any other cross-section that is desirable in light ofthe application.

According to certain embodiments of the invention, a technique isprovided whereby one or more elements of a laminated structure aresecured within the assembly without relying on an adhesive. One of skillin the art will appreciate certain materials that might otherwise bedesirable for use within an assembly, prepared according to theinvention, will be problematic because of bond issues. That is, somematerials are difficult to pair with an effective adhesive. This isespecially the case with some elastomeric materials, where poor bondingwill impair or prevent these materials from being integrated into alaminate assembly.

Consequently, in certain embodiments of the invention, it will beadvantageous to employ a mechanical fastener of one form or another tocouple one or more elements of the assembly together. Such a mechanicalfastener will, in particular embodiments, include a rivet, a screw, anut and bolt combination, a pin and cotter pin device, a spring clipdevice, a bolt and toggle arrangement, a screw and molly bolt device, orany other mechanical fastener or mechanical fastening system such as isknown or becomes known in the art.

One of skill in the art will appreciate that such a mechanical fastenerwill, in certain embodiments, be used in combination with an adhesivematerial, and that a variety of mechanical fasteners may be used incombination with one another, each combination corresponding to therequirements of a particular application.

In certain methods and embodiments, a mechanical fastener will beemployed to couple the elements of one portion of an overall assembly toone another while a subsequent process coupled further elements to theassembly. The subsequent process may include additional mechanicalfasteners, adhesive materials, and/or any other appropriate couplingmechanism (e.g., electric spot welding, ultrasonic welding, laserwelding, etc.). In certain moments, the one portion of the overallassembly will constitute a subassembly.

In still further embodiments of the invention, a portion of one or moremechanical fasteners will beyond an outer surface of a subassembly andbe effective as a fixturing pin or dowel to assist in or effect thealignment of further assembly elements during assembly. Again, thefurther assembly elements may be coupled to the balance of the assemblyby use of the same fixturing pin as a mechanical fastener, and/or by theaddition of an adhesive or any other bonding means such as describedabove and/or is known in the art.

In still further embodiment of the invention, one or more mechanicalfasteners are employed in the process of preparing a subassembly and/oran assembly. Thereafter, at some point in the course of assembly and/orusing the resulting device, that mechanical fastener is removed, orotherwise displaced from the assembly. Thereafter, the integrity of theassembly will, in certain embodiments, be maintained by another teacher,such as a further mechanical fastener, adhesive, or any other bonding asdescribed.

Mechanical fasteners will, in appropriate embodiments, have a variety ofcharacteristics appropriate to the particular application. Thus, incertain applications, the mechanical fastener will be includeelectrically conductive conducted material, an optically conductivematerial, an insulating material and/or an opaque material, a thermallyconductive material and/or a thermally insulating material. In certainembodiments, a mechanical employed in a device according to principlesof the invention will include any appropriate material including, forexample and without limitation, a metallic material (e.g., stainlesssteel, mild steel, high-speed steel; alloys of nickel, titanium,aluminum, and rare earth metals, taken alone or in combination),polymeric material including natural and synthetic polymers; andinorganic material, or any other beneficial material or combination ofmaterials.

Mechanical fasteners will also, in appropriate circumstances, have avariety of geometric characteristics including, for example, a circularcross-section, a triangular cross-section, a square cross-section,rectangular cross-section, any other polygonal cross-section, ellipsoidcross-section, a stellate cross-section, or any other cross-section orcombination of cross-section. Likewise, mechanical fasteners will betapered or otherwise configured to match the needs of a particularapplication.

FIG. 12A shows, in schematic side view, further features of an assembly1200 produced according to principles of the invention. In particular,assembly 1200 includes a plurality of mechanical bonding elements 1202,1204, 1206. In the illustrated embodiment, these bonding elements areshown as rivets but, in view of the foregoing, one of skill in the artwill appreciate that one or more of the same may be a differentmechanical fastener.

FIG. 12B shows, in schematic side view, the assembly 1200 according to afirst embodiment and including a rivet 1202. The rivet 1202 includes, inthe illustrated embodiment, a head portion 1204 extending below a lowersurface 1206 of the laminate assembly. The rivet 1202 is disposed withinrespective bores 1208, 1210 and 1212 of corresponding layers 1214, 1216and 1218 of the laminate assembly. One of skill in the art willappreciate that, after assembly, and in certain moments with the layersunder external pressure, an upper end 1220 of the rivet 1202 will bedeformed by the application of, for example, mechanical force to securethe rivet in place and maintain the layers in intimate contact withthose adjacent.

FIG. 12C shows a further embodiment of the invention in which a rivet1202 is disposed within respective bores 1208, 1210. Layer 1218,however, has a configuration such that the rivet 1202 is disposedoutwardly of an external edge, or within a larger aperture, of thatlayer and not within a constricted bore of the same. In such anembodiment, layer 1218 may, for example, be bonded adhesively to layer1216, maybe held in place by the mechanical fasteners, or may have someability to move with respect to layer 1216, e.g. by translation into thesurface of the drawing.

It will be appreciated that, although the rivets just illustrated areshown to be disposed completely through the assembly, in otherembodiments, a mechanical fastener may be arranged to be disposedthrough only a portion of an assembly. For example, it may have a lengththat is shorter than a height of the assembly.

In a further aspect of the invention, the riveting technique may be usedto store energy within laminate. Holes or bores in riveted material canbe located such that one or more material must be inelastically orelastically deformed before engaging with posts or pins. Suchdeformation may be tensile, compressive, torsional, or any combinationof the same. By such a technique, elastic energy can be stored inriveted material. This stored energy may serve, among other purposes, toactivate a folding process or provide a restoring force for adisplaceable subassembly.

In certain instances it will be beneficial to employ a bearing devicethat allows a more complete rotation than, for example, the torsionhinge described above in relation to FIG. 9 . In such an embodiment, theapplication of a bearing, such as a rotary bearing, in combination withother features of the invention will have surprising benefits.

FIG. 13 shows, in cutaway perspective view, a mechanical bearingassembly 1300, exemplary of many possible bearing configurations thatwill be employed in various corresponding configurations and embodimentsprepared according to principles of the invention. The illustratedbearing includes an inner race 1302, and outer race 1304, and aplurality of individual bearings, e.g., 1306, 1308, 1310. Theillustrated individual bearings are shown as spherical roller bearings,but one of skill in the art will appreciate that any of the wide varietyof other bearing configurations will be readily beneficially employed incorresponding embodiments of the invention. Thus, for example, incertain embodiments, one or more of a ball bearing, a roller bearing, aneedle bearing, a pushing, a magnetic bearing, an electrostatic bearing,a ferrofluidic bearing, an air bearing or other hydrodynamic bearing, orany other bearing arrangement that is known, or that becomes known inthe art will be advantageously employed.

The illustrated bearing assembly also includes a bearing holder 1312that maintains a desirable spacing of the individual bearings in amanner well known in the art. The inner race 1302 has an innercircumferential surface region 1314 and, for example, first 1316 andsecond 1318 radial surface regions. In like fashion, the outer race 1304has an external circumferential surface region 1320 and first 1322 andsecond 1324 radial surface regions.

FIG. 14 shows, in schematic side view, a portion of apparatus 1400prepared according to principles of the invention. The illustratedapparatus includes first 1402, second 1404, third 1406 and forth 1408generally planar and substantially rigid members or layers of material.

Layer 1404 includes an inner circumferential surface region 1410 thatdefines an aperture in that layer. Circumferential surface region 1410,in conjunction with a corresponding upper surface region 1412 of layer1402, defines an aperture 1414 within which a portion of an inner race1416 of a bearing device 1418 is disposed and within which the innerrace can turn freely. An outer race 1420 of bearing device 1418 includesa radial surface region 1422 that is disposed adjacent to and supportedby a corresponding upper surface region 1424 of layer 1404.

Layer 1406 includes an internal circumferential surface region 1426defining a further aperture or cavity 1428 that accommodates bearingdevice 1418. A further radial surface region 1430 of inner race 1416 isdisposed adjacent to and arranged to support a corresponding lowersurface region 1432 of layer 1408. In certain embodiments, an axialdimension 1434 of the bearing device is arranged in conjunction with acumulative thickness 1436 of layers 1404 and 1406 so as to maintain adesirable spacing 1438 between an upper surface region 1440 of layer1406 and an adjacent lower surface region 1442 of layer 1408. In otherembodiments, the surface region will be in contact, but will havematerial characteristics that result in desirable levels the frictionbetween the two layers.

It will be noted that adhesive layers are omitted from the foregoingdiscussion of FIG. 14 so as to reduce the complexity of thatpresentation and improve clarity. One of skill in the art willappreciate that any desirable adhesive or fixturing mechanism will beemployed vis-à-vis the various layers and/or the bearing device. It willalso be understood that, in certain embodiments, characteristics of theraise layers will be selected for particular desirable properties. Thus,for example, in a certain embodiment, layer 1404 may be less rigid than,e.g., adjacent layers 1402 and 4006. Consequently, layer 1404 willprovide a shock absorbing characteristic to the illustrated mounting ofthe bearing device 1418.

Of course it will be appreciated that illustrated arrangement will, incertain embodiments, allow a substantially unrestricted rotary motion1444 of layer 1408, with respect to the balance of the illustratedlayers, around a longitudinal axis 1446 of the bearing device 1418. Apractitioner of ordinary skill in the art will appreciate that a bearingdevice 1418 will, according to certain aspects of the invention, bedeposited in an aperture 1414, 1418 using well known pick-and-placemanufacturing techniques.

FIGS. 15A, 15B and 15C show various miniature bearing devices andarrangements that will form novel and beneficial combinations withcorresponding embodiments of the present invention. For example, FIG.15A shows a “jewel bearing” device 1500 that will be employed in certainembodiments prepared according to principles of the invention. The jewelbearing device includes a jewel portion 1502 formed of a hard and robustmaterial such as, for example, diamond, ruby, emerald quartz, etc. Thejewel portion 1502 is disposed smugly within an aperture formed by aninner circumferential surface region 1504 of a layer 1506 of, e.g.,substantially rigid material. In certain embodiments, and adhesive willbe provided between the jewel portion 1502 and surface region 1504 toensure a substantially permanent fixation of the spatial relationshipbetween the two.

In the illustrated embodiment, the jewel portion 1502 includes a furtherinternal circumferential surface region 1508 which defines an aperture.Disposed within this aperture is a shaft 1510 with an externalcircumferential surface region disposed adjacent to and supported bysurface region 1508. In certain embodiments, a lubricant material 1512is disposed adjacent to shaft 1510 and surface region 1508. Thelubricant will be, in various embodiments, a dry lubricant material, aliquid lubricant material, gaseous lubricant material, or any otheravailable material appropriate for particular circumstances. Thelubricant well, in corresponding embodiments, be held in place bysurface tension/capillary action, gravity, where orientation of theassembly is appropriate, magnetic force, etc.

FIG. 15B shows a more complex bearing device 1540. Bearing device 1540includes a first jewel portion 1542 and a second jewel portion 1544.Second jewel portion 1544 includes a surface region 1546 range tointerface with a corresponding radial surface region at an end of ashaft 1550. Consequently, this arrangement provides a superior provisionof alignment of the shaft when used for its thrust bearing capability,as compared with device 1500. Again, an optional lubricant material 1552is shown disposed within a cavity 1554.

FIG. 15C shows, with a plurality of arrows, locations in which jewelbearings are used in a conventional mechanical watch assembly.

FIGS. 16A, 168 and 16C illustrate certain characteristics of an assemblyincluding a clamped joint prepared according to principles of theinvention. FIG. 16A shows a hinge device 1600 prepared according toprinciples of the invention like that illustrated in FIG. 4B above. Thehinge device includes first 1602 and second 1604 substantially rigidlayers, a substantially flexible layer 1606 and first 1608 and second1610 adhesive layers. Respective terminal end surface regions 1612, 1614of layers 1602 and 1604 are visible.

FIG. 168 shows, in additional detail, hinge device 1600 includingsubstantially rigid layers 1602 and 1604 adjacent terminal end surfaceregions 1612 and 1614. It will be apparent on inspection that layers1602 and 1604 are not in intimate contact with corresponding surfaceregions 1616, 1618 of flexible layer 1606, but are separated from it bythe intervening adhesive layers 1608 and 1610.

FIG. 16C shows an alternative embodiment 1650 of the invention in whichterminal end portions 1620, 1622 of layers 1602 and 1604 are disposed inintimate contact with flexible layer 1606 at respective surface regions1624 and 1626. This arrangement provides additional support for theflexible layer 1606, vis-à-vis the rigid layer 1602 and 1604.Consequently, strength, endurance, repeatability and precision of theresulting hinge will, in certain embodiments, be improved.

FIGS. 17A, 17B and 17C show alternative clamped joint arrangementsprepared according to principles of the invention. In FIG. 17A thinlayers of substantially rigid material 1702, 1704 and respective thinadhesive layers 1706, 1708 cooperate to form a clamped region offlexible member 1710 between outer rigid layers 1712 and 1714. FIG. 17Billustrates an arrangement 1720 in which flexible layer 1722 includes anaperture or hole 1724. An adhesive material 1726 is disposed within thehole and in contact with internal surface region 1726, 1728 ofrespective substantially rigid layers 1730, 1732. As is evident oninspection, rigid layer 1730 and 1732 are deformed at respective regions1734, 1736 so as to bring further surface regions 1738 and 1740 intosupporting contact with flexible layer 1722. One of skill in the artwill appreciate that adhesive material 1726 will serve to further locateand stabilize flexible layer 1722 with respect to substantially rigidlayers 1730 and 1732, and thus tend to improve the overall precision andstability of the resulting joint.

FIG. 17C shows a further configuration 1750 that is generally similar to1720. In configuration 1750, however, flexible layer 1722 includes anaperture 1752 in proximity to surface regions 1738 and 1740. An adhesivematerial 1754 is disposed within aperture 1752 to further stabilize theinterface between the flexible layer 1722 and substantially rigid layers1730 and 1732.

FIGS. 18A, 18B, 18C and 18D illustrate certain characteristics of anassembly including a multi-leaf joint prepared according to principlesof the invention. FIG. 18A shows a hinge device 1800 prepared accordingto principles of the invention like that illustrated in FIG. 4B above.The hinge device includes first 1802 and second 1804 substantially rigidlayers, a substantially flexible layer 1806 and first 1808 and second1810 adhesive layers. Respective terminal end surface regions 1812, 1814of layers 1802 and 1804 are visible.

FIG. 18B shows, in additional detail, hinge device 1800 includingsubstantially rigid layers 1802 and 1804 adjacent terminal end surfaceregions 1812 and 1814. It will be apparent on inspection that flexiblelayer 1806 is a single monolithic layer.

FIG. 18C shows an alternative arrangement 1820 in which the flexiblelayer includes a laminated assembly with a plurality of thin flexiblelayers 1822, 1824, 1826 and 1828, and spaces 1830, 1832 and 1834. Thismulti-leaf flexure joint is accordingly created from two or more layersof material. A single flexure material can be used or differentmaterials can be used to create a heterogenous flexure. Multi-leafflexures can be combined with other enhancements such as the clampedjoint as shown in FIG. 18D.

Without intending to be bound to a particular theory of operation, themulti-leaf flexure joint is believed to be characterized by lower peakbending stress as compared to a standard flexure joint. The bendingelement is divided into multiple layers able to slide against oneanother in shear. A similar methodology is used in leaf springs, amainstay of automobile and truck suspensions. Multi-leaf joints will, incertain embodiments, have much longer lifetimes as compared to singleleaf joints with the same net thickness of flexure material.

FIGS. 19, 20A, 20B, 21 and 22 illustrate certain characteristics of amultilayer joint prepared according to principles of the invention. Amultilayer joint is distinguished from a multi-leaf joint inasmuch asthe layers (longitudinal members 1902) of a multilayer joint aredisposed in parallel to one another and in orientation generallyperpendicular to the respective planes of the members being rotationallycoupled. The layers of a multi-leaf joint, on the other hand, aregenerally parallel with the planes of the members being rotationallycoupled.

In brief, the multilayer joint is a novel arrangement of an arbitrarynumber of bending elements, or joints, interconnected in a manner suchthat the complete arrangement functions as a single effective joint withone degree of freedom. The motion of this combined joint is not a purerotation: instead motion approximates the output of a serial chain oftwo links with both joint angles constrained to be equal in magnitudeand sign.

This design increases robustness by lowering the bend angle of eachindividual joint while greatly reducing off-axis stresses on each. Thisdesign can easily produce a joint that withstands 8 x the off-axistorque before failure while halving peak joint bending angle, all withinthe same footprint.s′(θ)=√{square root over (l ²−cos² θt ²)}s(θ)=√{square root over (l ²−cos² θt ²)}+2ϵ cos θs ₀ =s(θ=0)=√{square root over (l ² −t ²)}+2ϵ

Start with a base s₀, t₀, ϵ₀ A starting point is s₀=2 mm, t₀=200 μm, andϵ₀=0. A simple linkage constructed according to FIG. 19 will exhibitperfect motion. However, multiple such linkages using different laminate(substrate 1904) layers (t is allowed to vary in discrete steps) can becombined with the same input (first endplate 1906) and output beams(second endplate 1908) with minimal deviation from the ideal case. Thereare many ways to minimize this deviation.

A first test case, we can set that the combined linkage is perfect attwo points, start θ=0 and finish θ=θ_(f)=90°, which definess_(f)=s(θ_(f)) for the base joint. We pick different laminate layers forthe joints, defined by a new thickness t₁. We maintain the original s₀to fix the same rotation point: this in essence binds the input andoutput beams of the combined linkage. We then solve for e by taking thelesser of two solutions to the quadratic equation:0=(s ₀ ² −s _(f) ²+sin²θ_(f) t ₁ ²)+4(s _(j) cos θ−s ₀)ϵ+(4 sin²θ)ϵ²

Looking at FIGS. 20A and 20B gives some insight. On the right, we seedeviation from ideal for designs with t increasing in increments of 200μm. With a 400 μm increase in t, there is a peak deviation of less than2 μm occurring around 620.

There are many other ways to alter E for each linkage to obtaindesirable properties. One can optimize to minimize axis drift in somefashion across the whole motion, not just the endpoints. One can alsomanipulate ϵ values to reduce mechanical interference of the combinedlinkage, with ϵ=0 across all linkages a notable design point.

FIG. 21 shows in schematic form, an example of a multilayer jointincluding three base linkages. FIG. 22 shows in schematic perspectiveview, an exemplary practical implementation of one embodiment of amultilayer joint.

FIG. 23 shows, in schematic form, a further implementation of amultilayer joint prepared according to principles of the invention. Theillustrated multilayer joint is one in which many joint and theirassociated links combined to create an output link that translates alonga circular arc without rotation. Such a design is a useful subcomponentof a larger linkage. Furthermore, it arbitrarily scales to any evennumber of joints, with larger joint count leading to increased movementprecision and increased robustness.

FIG. 23 illustrates a four linkage layer embodiment of this arrangementof joints, involving eight joints. Two linkage layers (for joints) arethe minimum to ensure 1° of freedom motion. Notably, this design can beextended, without obligation, to an arbitrary number n of linkage layersinvolving 2n joints. The magnitude of off-axis torque is designed towithstand before failure scales approximately linearly with n, hugelyincreasing mechanism robustness. Furthermore, this design increasesmotion precision by connecting multiple linkages in parallel, averagingtheir output motion.

In one specific embodiment, eight instances of this arrangement ofjoints can be combined to create a larger linkage whose outputtranslates along a straight line without rotation, similar to a Ferrishinge or scissors jack. Such linear motion is useful, e.g., for movingmirrors or lenses in optical systems. Representation of this embodimentis provided in various states of operation in FIGS. 24A-24C.

FIG. 25 shows, in cross-sectional view, a further aspect and embodimentof the invention including a portion of a joint 2500. In the exemplaryembodiment of FIG. 25 the hinge includes a first substantially flexiblelayer 2502. First 2504 and second 2506 layers of adhesive material aredisposed in intimate contact with respective upper and lower surfaceregions of the first substantially flexible layer 2502. First 2504 andsecond 2506 layers of adhesive material are disposed in intimate contactwith respect to lower 2508 and upper 2510 surface regions ofsubstantially rigid upper 2512 and lower 2514 layers of material.

As is evident from the figure, the substantially flexible layer 2502extends across a medial plane 2516 of the joint 2500. Likewise, furtherportions 2518, 2520 of first 2504 and second 2506 substantially rigidlayers are disposed across the medial plane, and coupled to thesubstantially flexible layer 2502 by respective portions 2522, 2524 ofthe adhesive layers 2504 and 2506.

As illustrated in FIG. 25 , and surfaces 2526, 2528, 2530, 2532 of thesubstantially rigid layers 2512, 2514 are relieved from theperpendicular at a relief angle, e.g., 2534. For purposes of thisdescription (and without limiting in any way the configuration that anactual joint prepared according to principles of the invention willbehave subject to and in the absence of external forces), theconfiguration of joint 2500 illustrated in FIG. 25 will be denominatedthe “relaxed” configuration.

FIG. 26 illustrates a joint 2600 that is similar to joint 2500 of FIG.25 . Joint 2600 is shown in a flexed configuration, illustrating onemode of operation of the joint. It will be noted that no mechanicalinterference is exhibited, by the illustrated configuration, between therelieved surface edges 2526 and 2528. This is in contrast to themechanical interference that would occur 2602 if the surface edges werenot relieved, but were in a perpendicular orientation as illustrated bydashed lines 2604, 2606.

FIG. 27 illustrates a joint 2700 exemplifying further aspects andembodiments of the invention. As illustrated, joint 2700 includes anedge surface 2702 that is relieved at a relief angle 2704. Other edgesurfaces, e.g., 2706, 2708, 2710 are not relieved, or are relieved atother relief angles, e.g. 2712, 2714 and 2716, respectively. Thus itwill be appreciated that the relief angles corresponding to a particularedge surface will be chosen in light of the particular circumstances inwhich the joint is applied. Indeed, in certain embodiments, the edgesurfaces will include features allowing interlocking of relief surfacesat the extreme end of a joints activation to provide additional supportand/or will include elastic features adapted to cushion the arrival ofthe joint at such an extreme position.

FIG. 28 shows a portion of an exemplary joint 2800 in perspective viewso as to further clarify the disclosure.

In preparing the device as described above, layers of metal, composite,polymer, etc., are machined or formed by virtually any method; andvirtually any material may be used. Example machining methods includelaser cutting from sheet material, photo-chemical etching, punching,electroforming, electric discharge machining, etc.—basically any methodthat has appropriate resolution and compatibility with the desiredmaterial.

Machined layers may then be subjected to additional processes, such ascleaning/etching to remove machining debris, plating (e.g., platingfluxed copper on a layer to facilitate adhesion of solder thereto),preparation for bonding, annealing, etc. The unified nature of eachlayer makes handling and post-processing easy. Advantageously, eachlayer can be a different material and can be machined and treateddifferently from each of the other layers.

Each layer can also advantageously be formed of a material that issufficiently rigid, strong and tough to allow holes for alignment pinsand other features to be machined into the layer, to facilitate easyhandling, and to not distort when placed into the layup and whenrestrained by alignment pins.

In other embodiments, layers that do not have the structural stabilityto support alignment features can nevertheless be used by attaching suchlayers, in bulk form, to a rigid frame that meets these objectiveswithout introducing enough additional thickness to disturb the otherlayers or parts in the laminate.

In particular examples, a very thin polymer film (e.g., 2-5 micronsthick) is included among the layers. Due to its thinness and insulatingqualities, the thin polymer film is prone to wrinkling and electrostatichandling issues. To address this tendency, the thin polymer film can belightly stretched, in bulk form, to a flat and controlled state and thenbonded to a thin frame that is made, for example, of thin metal orfiberglass composite. Next, the thin polymer layer can be machined withthe fine part features (e.g., tiny holes in the polymer at preciselocations), and the alignment hole features can be machined into theframe material.

In additional embodiments, the device can be designed to mitigatethin-layer handling issues. For example, a part within the device can bedesigned such that all machining pertinent to a fragile layer isperformed post-lamination; and, thus, this layer will not requireprecision alignment when put into the laminate, though the material isadvantageously capable of being placed into the laminate sufficientlyflat and extending over a sufficient area to cover the desired parts ofthe device.

In exemplary embodiments, bulk polymer films (formed, e.g., ofpolyester, polyimide, etc.); metal sheets and foils [formed, e.g., ofstainless steel, spring steel, titanium, copper, invar (FeNi36),nickel-titanium alloy (nitinol), aluminum, etc.]; copper-clad laminates;carbon fiber and glass fiber composites; thermoplastic or thermosetadhesive films; ceramic sheets; etc.; can be laser machined to make thelayers that are laminated to form the multi-layer structure. The lasermachining can be performed, e.g., with a 355-nm laser (from DPSS LasersInc. of Santa Clara, Calif.) with a spot size of about 7 microns onmaterials with typical thicknesses of 1-150-μm, although thicker layerscan be machined with such a laser, well. Accordingly, this type of laserallows for very high resolution and an ability to machine almost anytype of material.

Adhesion between layers is achieved by patterning adhesive onto one orboth sides of a non-adhesive layer or by using free-standing adhesivelayers (“bondplies”). In the latter case, an intrinsically adhesivelayer, e.g., in the form of a sheet of thermoplastic or thermoset filmadhesive, or an adhesive laminate, such as a structural material layerwith adhesive pre-bonded to one or both sides.

The adhesive layer is machined like the other layers. Specific examplesof sheets that can be used as the adhesive layer 14 include sheetadhesives used in making flex circuits (e.g., DuPont FR1500 adhesivesheet) or polyimide film coated with FEP thermoplastic adhesive on oneor both sides.

Free-standing sheet adhesives can be acrylic-based for thermosets;alternatively, the adhesive can be thermoplastic, wherein thethermoplastic film can be formed of polyester, fluorinated ethylenepropylene (or other fluoropolymer), polyamide, polyetheretherketone,liquid crystal polymer, thermoplastic polyimide, etc. Any of theseadhesives can also be applied on one or both sides to a non-adhesivecarrier. In additional embodiments, a layer may serve both as astructural layer and as a thermoset adhesive—for example, liquid crystalpolymer or thermoplastic polyimide. Furthermore, for special types ofstructural layers, a variety of wafer bonding techniques that do notrequire an adhesive may be employed, such as fusion bonding.

In another technique for achieving adhesion between layers, adhesive isapplied and patterned directly on a non-adhesive layer. This techniquecan be used where, for example, the type of adhesive desired may not beamenable to free-standing form. Examples of such an adhesive includesolders, which are inherently inclined to form a very thin layer, oradhesives that are applied in liquid form (by spraying, stenciling,dipping, spin coating, etc.) and then b-stage cured and patterned.B-staged epoxy films are commonly available, but they usually cannotsupport themselves unless they are quite thick or reinforced with scrim.

The resulting bond can be a “tack bond,” wherein the adhesive 14 islightly cross-linked to an adjacent layer before laser micromachiningwith sufficient tack to hold it in place for subsequent machining andwith sufficient strength to allow removal of the adhesive backing layer.The tack bonding allows for creation of an “island” of adhesive in apress layup that is not part of a contiguous piece, which offers asignificant increase in capability.

Another reason for tacking the adhesive to an adjacent structural layeris to allow for unsupported “islands” of adhesive to be attached toanother layer without having to establish a physical link from thatdesired adhesive patch to the surrounding “frame” of material containingthe alignment features. In one embodiment, a photoimagable liquidadhesive, such as benzocyclobutene, can be applied in a thin layer, softbaked, and then patterned using lithography, leaving a selective patternof adhesive. Other photoimagable adhesives used in wafer bonding canalso be used.

The adhesive is patterned while initially tacked to its carrier film,aligned to the structural layer using pins, and then tacked to at leastone adjoining layer in the layup with heat and pressure (e.g., at 200°C. and 340 kPa for one hour). Alternatively, the adhesively layer can bepatterned by micro-machining it as a free sheet.

Tack bonding can involve application of heat and pressure at a lowerintensity and for less time than is required for a complete bond of theadhesive. In yet another embodiment, the adhesive film can be tackbonded in bulk, and then machined using, for example, laserskiving/etching. Advantageously, use of this variation can be limited tocontexts where the machining process does not damage the host layer.Both of these variations were tried using DuPont FR1500 adhesive sheetand laser skiving.

To form the multi-layer laminate structure, a multitude of these layers(e.g., up to 15 layers have been demonstrated) are ultrasonicallycleaned and exposed to an oxygen plasma to promote bonding and alignedin a stack by passing several vertically oriented precision dowel pinsrespectively through several alignment apertures in each of the layers,and by using a set of flat tooling plates with matching relief holes forthe alignment pins. In other embodiments, other alignment techniques(e.g., optical alignment) can be used.

All layers can be aligned and laminated together. Linkages in thelaminated layers can be planar (where all joint axes are parallel); orthe joint axes can be non-parallel, allowing for non-planar linkages,such as spherical joints. In the fifteen-layer example, the final layupincluded the following layers, which formed a pair of linkages (i.e.,structures wherein flexible layers are bonded to rigid segments andextend across the gaps between the rigid segments, thereby enablingflexure of the rigid segments relative to one another at the flexiblelayer in the gaps between the rigid segments, wherein those exposedsections of the flexible layer effectively serve as joints.

Unless otherwise defined, used or characterized herein, terms that areused in this description (including technical and scientific terms) areto be interpreted as having a meaning that is consistent with theiraccepted meaning in the context of the relevant art and are not to beinterpreted in an idealized or overly formal sense unless expressly sodefined herein. For example, if a particular composition is referenced,the composition may be substantially, though not perfectly pure, aspractical and imperfect realities may apply; e.g., the potentialpresence of at least trace impurities (e.g., at less than 1 or 2% byweight or volume) can be understood as being within the scope of thedescription; likewise, if a particular shape is referenced, the shape isintended to include imperfect variations from ideal shapes, e.g., due tomachining tolerances.

Although the terms, first, second, third, etc., may be used herein todescribe various elements, these elements are not to be limited by theseterms. These terms are simply used to distinguish one element fromanother. Thus, a first element, discussed below, could be termed asecond element without departing from the teachings of the exemplaryembodiments.

Spatially relative terms, such as “above,” “upper,” “beneath,” “below,”“lower,” and the like, may be used herein for ease of description todescribe the relationship of one element to another element, asillustrated in the figures. It will be understood that the spatiallyrelative terms are intended to encompass different orientations of theapparatus in use or operation in addition to the orientation describedand/or depicted in the figures. For example, if the apparatus in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term, “above,” may encompass both anorientation of above and below. The apparatus may be otherwise oriented(e.g., rotated 90 degrees or at other orientations) and the spatiallyrelative descriptors used herein interpreted accordingly.

Further still, in this disclosure, when an element is referred to asbeing “on,” “connected to” or “coupled to” another element, it may bedirectly on, connected or coupled to the other element or interveningelements may be present unless otherwise specified.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting of exemplary embodiments.As used herein, the singular forms, “a,” “an” and “the,” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. Additionally, the terms, “includes,” “including,” “comprises”and “comprising,” specify the presence of the stated elements or stepsbut do not preclude the presence or addition of one or more otherelements or steps.

In presenting the descriptions above, reference has been made to be“super-planar structure.” By “planar,” we mean a layer or plane that canbe distorted, flexed or folded (these terms may be used interchangeablyherein). An embodiment of this structure can be achieved, for example,by forming a five-layer composite with the following sequence of layers:rigid layer, adhesive layer, flexible layer, adhesive layer, rigidlayer. Alternatively, a thinner composite can be formed from a stackingof just a rigid layer, an adhesive layer, and a flexible layer, thoughthis structure is not symmetric. The rigid layers are machined to havegaps that correspond to fold lines, while the flexible layer iscontinuous, thereby providing a joint where the flexible layer extendsacross the gaps machined from the rigid layers.

Characterization of the structure as being “super-planar” means takingmultiple planar layers and selectively connecting them. An analogy herecan be drawn to circuit boards, where electrical vias connect circuitson different layers. Here, in contrast, the structure is made with“mechanical vias.” By stacking multiple planar layers, the range ofachievable devices is greatly expanded. The super-planar structure alsoenables features and components to be packed into the structure thatwould not fit if the device could only be made out of one planar sheet.Advantageously, super-planar structures with mechanisms that operatenormal to the plane can now be made with these techniques. In practice,forming Sarrus linkages between planar layers is an advantageousstrategy for designing an assembly mechanism/scaffold. Other mechanismscan attach to the Sarrus links to effect the intended componentrotations.

The multi-layer super-planar structure can be fabricated via thefollowing sequence of steps: (1) machine each planar layer, (2) machineor pattern adhesives, (3) stack and laminate the layers under conditionsto effect bonding, (4) post-lamination machining of the multi-layerstructure, (5) post-lamination treatment of the multi-layer structure,(6) freeing an assembly degree of freedom in each structure, (7) lockingconnections between structural members, (8) freeing any non-assemblydegrees of freedom, and (9) separating finished parts from a scrapframe.

While the exemplary embodiments described above have been chosenprimarily from the field of assemblies of generally planar elements, oneof skill in the art will appreciate that the principles of the inventionare equally well applied, and that the benefits of the present inventionare equally well realized in relation to elements of otherconfigurations including, for example, elements having a cylindrical,ellipsoid or hemispherical curvature. Further, while the invention hasbeen described in detail in connection with the presently preferredembodiments, it should be readily understood that the invention is notlimited to such disclosed embodiments. Rather, the invention can bemodified to incorporate any number of variations, alterations,substitutions, or equivalent arrangements not heretofore described, butwhich are commensurate with the spirit and scope of the invention.Accordingly, the invention is not to be seen as limited by the foregoingdescription, but is only limited by the scope of the appended claims.

The invention claimed is:
 1. A multilayer joint element comprising: afirst endplate; a second endplate; a first longitudinal member; a secondlongitudinal member, said first and second longitudinal members havingrespective first ends, said respective first ends being connected tosaid first endplate diametrically across said first endplate from oneanother, and said first and second longitudinal members havingrespective second ends, said respective second ends being connected tosaid second endplate diametrically across said second endplate from oneanother, whereby said first and second longitudinal members are disposedin substantially parallel spaced relation to one another such that saidfirst and second ends of said first longitudinal member and said firstand second ends of said second longitudinal member togethersubstantially define a geometric rectangle; and wherein said first andsecond endplates and said first and second longitudinal members togetherform a substantially rigid structure; and wherein said firstlongitudinal member is adapted to be coupled through a first flexibleelement to a first substrate and said second longitudinal member isadapted to be coupled through a second flexible element to a secondsubstrate such that said substantially rigid structure is adapted tosupport a pivotal motion about said multilayer joint element of saidsecond substrate with respect to said first substrate.
 2. A multilayerjoint element as defined in claim 1 wherein said first endplate and saidsecond endplate each comprise a plurality of layers of substantiallyrigid material.
 3. A multilayer joint element as defined in claim 1wherein said endplate has a substantially planar first inner surfaceregion and a substantially planar first outer surface region and whereinsaid substantially planar first inner surface region is disposed insubstantially parallel spaced relation to said first substantiallyplanar first outer surface region.
 4. A multilayer joint element asdefined in claim 3 wherein said second endplate has a substantiallyplanar second inner surface region and a substantially planar secondouter surface region, said substantially planar second inner surfaceregion being disposed in substantially planar spaced relation to saidsubstantially planar second outer surface region, and wherein saidsubstantially planar second inner surface region is disposed insubstantially parallel spaced relation to said substantially planarfirst inner surface region.
 5. A multilayer joint element as defined inclaim 4 wherein said multilayer joint element is disposed within afurther multilayer joint element, thereby forming a multilayer joint. 6.A multilayer joint element as defined in claim 5 wherein said first andsecond longitudinal members of said multilayer joint element includerespective extended portions beyond said respective first ends and saidrespective second ends.
 7. A multilayer joint element as defined inclaim 3 wherein said substantially planar first outer surface region hasa generally rectangular peripheral edge with a first protrusionproximate said first longitudinal member and a second protrusionproximate said second longitudinal member, said first protrusiondefining a first protrusion axis and said second protrusion defining asecond protrusion axis.
 8. A multilayer joint element as defined inclaim 7 wherein said first longitudinal member has a first longitudinalaxis and wherein said second longitudinal member has a secondlongitudinal axis and wherein said first protrusion axis in combinationwith said first longitudinal axis defines a first geometric plane andsaid second protrusion axis in combination with said second longitudinalaxis defines a second geometric plane, said first geometric plane andsaid second geometric plane being disposed in substantially parallelspaced relation to one another.
 9. A multilayer joint element as definedin claim 1 wherein a coupling of said first flexible element to saidfirst longitudinal member is disposed diametrically across saidmultilayer joint element from a coupling of said second flexible elementto said second longitudinal member.
 10. A multilayer joint element asdefined in claim 1 wherein a center point of a line segment drawnbetween said respective first ends, of said first and secondlongitudinal members, is adapted to traverse an arcuate curve duringoperation of a joint including said multilayer joint element.
 11. Amultilayer joint assembly comprising: a first substrate assembly, saidfirst substrate assembly including a first top layer, a second bottomlayer and a plurality of layers disposed between said first top layerand said second bottom layer; a second substrate assembly, said secondsubstrate assembly including a third top layer, a fourth bottom layerand a further plurality of layers disposed between said third top layerand said fourth bottom layer; a first joint element, said first jointelement including a first longitudinal member and a second longitudinalmember, said first and second longitudinal members being maintained insubstantially parallel spaced relation to one another by at least afirst substantially rigid body substantially fixedly coupledtherebetween, said first longitudinal member being disposed adjacent to,and flexibly coupled to said first top layer, said second longitudinalmember being disposed adjacent to, and flexibly coupled to, said fourthbottom layer; a second joint element, said second joint elementincluding a third longitudinal member and a fourth longitudinal member,said third and fourth longitudinal members being maintained insubstantially parallel spaced relation to one another by at least asecond substantially rigid body substantially fixedly coupledtherebetween, said third longitudinal member being disposed adjacent to,and flexibly coupled to said third top layer, said fourth longitudinalmember being disposed adjacent to, and flexibly coupled to, said secondbottom layer; whereby said first joint element is adapted to form apivotal coupling diagonally between said first top layer of said firstsubstrate and said fourth bottom layer of said second substrate, andwhereby said second joint element is adapted to form a pivotal couplingdiagonally between said third top layer of said second substrate andsaid second bottom layer of said first substrate.
 12. A multilayer jointassembly as defined in claim 11 wherein said first top layer, saidsecond bottom layer, and said plurality of layers disposed between saidfirst top layer and said second bottom layer include respectivesubstantially rigid layers of structural material.
 13. A multilayerjoint assembly as defined in claim 12 further comprising a respectiveplurality of layers of adhesive material disposed between saidsubstantially rigid layers of structural material respectively.
 14. Amultilayer joint assembly as defined in claim 11 wherein said firstsubstantially rigid body comprises a plurality of layers ofsubstantially rigid structural material.
 15. A multilayer joint assemblyas defined in claim 11 further comprising a layer of substantiallyflexible material mutually coupled to said first substrate assembly andto said first longitudinal member, whereby said first longitudinalmember is disposed adjacent to and flexibly coupled to said first toplayer.
 16. A multilayer joint assembly as defined in claim 11 whereinsaid first body includes a first body surface region, said first bodysurface region defining a first geometric plane, said first geometricplane being disposed substantially mutually normal to respectivelongitudinal axes of said first longitudinal member and said secondlongitudinal member; and wherein said second body includes a second bodysurface region, said second body surface region defining a secondgeometric plane, said second geometric plane being disposedsubstantially mutually normal to respective longitudinal axes of saidthird longitudinal member and said fourth longitudinal member, saidsecond geometric plane being disposed in substantially parallel spacedrelation to said first geometric plane such that said first body memberdoes not interfere with said second body member during operation of saidmultilayer joint assembly.
 17. A multilayer joint assembly as defined inclaim 16 wherein said first top layer defines a third geometric planeand wherein said third top layer defines a fourth geometric plane,wherein said first geometric plane and said second geometric plane aredisposed substantially normal to said third geometric plane and saidfourth geometric plane.
 18. A multilayer joint assembly as defined inclaim 11 wherein said first body member and said second body member areadapted to engage one another in sliding relation during operation ofsaid multilayer joint assembly.
 19. A method of preparing a multilayerjoint assembly comprising: providing a first substrate element, a secondsubstrate element and a third substrate element, said first substrateelement having a substrate surface region, said substrate surface regiondefining a geometric plane, said third substrate element having afurther surface region, said further surface region defining a furthergeometric plane; providing a first multilayer joint, said firstmultilayer joint including a first longitudinal member and a secondlongitudinal member, said first and second longitudinal members beingsubstantially fixedly disposed in substantially parallel spaced relationto one another, said first multilayer joint being operatively coupledbetween said first substrate element and said second substrate elementand adapted to allow rotation of said second substrate element in acounterclockwise rotation with respect to said first substrate element;providing a second multilayer joint, said second multilayer jointincluding a third longitudinal member and a fourth longitudinal member,said third and fourth longitudinal members being substantially fixedlydisposed in substantially parallel spaced relation to one another, saidsecond multilayer joint being operatively coupled between said secondsubstrate element and said third substrate element and adapted to allowrotation of said third substrate element in a clockwise rotation withrespect to said second substrate element; whereby upon operation of saidmultilayer joint assembly, said further substrate surface regiontranslates along a circular arc without rotation such that said secondgeometric plane remains disposed substantially parallel to said firstgeometric plane.
 20. A method of preparing a multilayer joint assemblyas defined in claim 19, further comprising incorporating said multilayerjoint assembly into a sarrus hinge assembly.